The Impact of Climate Change on Aeromedical Retrieval Services in Remote Northern Australia: Planning for a Hotter Future.

It is known that environmental heat is associated with increased morbidity manifesting as increasing demand on acute care health services including pre-hospital transport and emergency departments. These services play a vital role in emergency care, and in rural and remote locations, where resource capacity is limited, aeromedical and other retrieval services are a vital part of healthcare delivery. There is no research examining how heat impacts remote retrieval service delivery. The Northern Territory (NT) of Australia is characterised by very remote communities with limited acute healthcare capacities and is a region subject to regular extreme tropical heat. In this study, we examine the relationship between aeromedical retrievals and hot weather for all NT retrievals between February 2018 and December 2019. A regression analysis was performed on the number of retrievals by clinical reason for retrieval matched to the temperature on the day of retrieval. There was a statistically significant exposure response relationship with increasing retrievals of obstetric emergencies in hotter weather in the humid climate zone and surgical retrievals in the arid zone. Retrieval services appeared to be at capacity at all times of the year. Given that there are no obstetric services in remote communities and that obstetric emergencies are a higher triage category than other emergencies (i.e., more urgent), such an increase will impede overall retrieval service delivery in hot weather. Increasing surgical retrievals in the arid zone may reflect an increase in soft tissue infections occurring in overcrowded houses in the hotter months of the year. Given that retrieval services are at capacity throughout the year, any increase in demand caused by increasing environmental heat will have broad implications for service delivery as the climate warms. Planning for a hotter future must include building resilient communities by optimising local healthcare capacity and addressing housing and other socioeconomic inequities that amplify heat-related illness.